1. Field of the Invention
The invention relates to a circuit for synchronizing the oscillation of an oscillator keyed by a pulse, with a reference oscillation which has a relatively low amplitude and which is input-coupled into the oscillator, employing a phase regulating loop with a phase discriminator which is supplied, on the one hand, with a branched portion of the oscillator output oscillation and, on the other hand, is simultaneously supplied with the reference oscillation, and which compares the phase states of these two oscillations and emits a resultant regulating voltage for the control of an adjustable reactance for the frequency modification of the oscillator keyed by a pulse actually during the leading edge of the pulse, and more specifically where a phase shift device which can be adjusted up to 180.degree. is connected between the oscillator and the phase discriminator, and the high-ohmic output of the phase discriminator is connected in low-ohmic fashion via an impedance converter to the adjustable reactance.
2. Description of the Prior Art
A synchronizing circuit of this general type is described in the German allowed and published application No. 25, 32, 004.
In the circuit described in this German application, with every pulse of a pulse train, it is necessary for the phase regulating loop to build-up again and to again compensate the entire frequency error of the oscillation of the oscillator relative to the reference oscillation.